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carbon got milky from wetsanding

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plummet
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Re: carbon got milky from wetsanding

Postby plummet » Fri Sep 24, 2021 9:35 am

Don't sand it anymore. The milkyness in my opinion is the reasin layer still intact. The non milky is you sanding into the carbon weave.
You could go to the extent of re-resining and sanding. However that will give you the opportunity to remove more carbon when you start sanding again.

Go out and ride and disregard the milkyness.

AndersP
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Re: carbon got milky from wetsanding

Postby AndersP » Fri Sep 24, 2021 1:41 pm

1.Clean it.

2.Fill the scratches with epoxi/carbon or other filler. Try fill it until the scratch id completely filled. You may have to repeat if there is still some small cavity left.

3. Sand it but only to get a smooth surface, not more!

4. Just like 3 but with smaller grain paper

5. Like 4 and keep on with finer paper until you have smooth nice surface.

Don't sand more than that!

wavy navy
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Re: carbon got milky from wetsanding

Postby wavy navy » Fri Sep 24, 2021 2:01 pm

@AndersP: I did exactly what you suggested but exaggerated it. Can I use a 2k epoxy resin spray to get a new coat around it? I don't want to paint it with resin with a brush because I am afraid that it won't be consistently filled in the same thickness all over the area.

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Re: carbon got milky from wetsanding

Postby jonysan » Fri Sep 24, 2021 5:48 pm

Hi Wavy navy, If you are not bothered about keeping the carbon weave showing, then a quick way to get a good finish is to spray a couple of coats of Hi Build undercoat/primer from a rattle can, lay it on thick, then block sand it back until the black foil shows through in lots of places, you will have filled the low spots with Hi Build undercoat/primer, and levelled the surface. go steady on the concave curves as you might not get into them with a block.
Then one coat of black or colour of choice.
If you want the carbon weave to show, then paint a generous coat of clear resin, and block sand back, a Lot more work! and you will probably need to do that a couple of times to get adequate thickness. and it will take a day of waiting for each resin coat to harden !

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Re: carbon got milky from wetsanding

Postby alpaia » Thu Sep 30, 2021 7:17 am

Hi Wavy navy,
I would tend to agree with advices before - it is likely that you are very close or touching the weave so in doubt do nothing abrasive + "mirror" is not the best for a foil.

The finish you had was more likely a hard PU varnish or a very thin coat of fluid epoxy (formulated to behave like varnish, not thick epoxy) that could not take sanding.

An epoxy coat + sanding + polishing is difficult and takes practice to achieve properly and could turn out disastrous if you get fisheyes, uneven thickness etc.

So a filler coat as suggested before would be a much easier solution - even coat, easy to sand and different color/texture warning you before you sand into carbon etc

wavy navy
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Re: carbon got milky from wetsanding

Postby wavy navy » Thu Sep 30, 2021 7:29 am

Thanks jonysan and alpaia, right now I leave it as it is. The foil feels nice in the water and how it looks like is not that important I think...


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